1. Field of the Invention
This invention pertains to article carriers generally, and particularly to multi-purpose ski and bicycle carriers that engage a trailer type receiver hitch.
2. Description of the Related Art
Passenger vehicles are well adapted to transport people, as they were designed to do, and will readily transport small cargo such as grocery sacks and brief cases. People, however, do not always choose to rely upon passenger vehicles for transportation. During outings, such as week-end trips, vacations or competitions, other modes of transportation are often desired. Skis, canoes or bicycles may be integral to the outing. The recreational enthusiast knows the value of quiet leisure away from the hustle and bustle of the city, but must somehow find a way to carry both passengers and additional transportation equipment to the place of leisure. The competitor must get to and from the competitions, and will want to preserve the equipment for competition.
The method of transporting equipment should not detract from the goal of the outing, be it leisure or competition, nor should it cause any damage to the passenger vehicle. Unfortunately, in the past these simple goals have each been contrary to each other. A multitude of roof-top racks and carriers have been designed for either permanent or temporary mounting. These carriers are usually designed and manufactured to be compatible with one or a limited number of vehicles, since each vehicle is sized and shaped uniquely.
While the permanent variety usually are more reliable in load carrying, they are also usually installed at the factory to carefully control installation and thereby prevent any leakage or damage which might otherwise occur. Moreover, they permanently add to the size of the vehicle, and also generally detract from the vehicle's appearance.
Temporary carriers have been designed from diverse materials and geometries, including materials such as foam block, foam pad, rubber, plastic, metal and wood. To reduce the inventory required by a vendor to sell the temporary carrier, common vehicle features are used to attempt to provide the necessary support for cargo. For example, gutters are often found around vehicle doors, and a number of carriers clamp onto these gutters. Unfortunately, not all vehicles have features such as gutters, and so several different carriers must still be designed. Other carriers rely on the roof of the vehicle to provide both load bearing and also a place for friction, suction or magnetic grab. These temporary carriers have a tendency to be more temporary than planned or desired, occasionally allowing the cargo to slip and either be damaged or damage the vehicle. Such an event is totally unacceptable and will render a carrier useless.
In addition to the other challenges, roof-top carriers present an obstacle during loading and unloading. The equipment must somehow be placed on top of the vehicle without damaging either the vehicle or the equipment. Yet, the reason the equipment is being placed on top of the vehicle is because of large size and/or great bulk.
Other prior art carriers have been designed to mount on the bumper of a vehicle. While this type of carrier is often easier to load and unload, the limitations related to different vehicle designs found with the roof top carriers are still present. Different vehicles have different bumper designs. Some of the most modem vehicles offer no access to the bumper at all, and so different carriers must still be designed and stocked to accommodate different vehicles.
Given the limitations of the prior art, it is not surprising that there has been a relative explosion in carriers designed to install directly into a hitch receiver. The hitch receiver acts as a universal coupling into which utility and boat trailers may be attached, and may also be used to support a carrier. Like the bumper carrier, a hitch receiver carrier provides the advantage of easy equipment loading. In addition, hitch receivers have become standard to two sizes. The large size, a two inch receiver, is designed for high loads and may be specified, for example, for trailers as large as 3,500 pounds and tongue weights as great as 350 pounds. For smaller loads, typically up to 2,000 pounds and tongue weights of 200 pounds, a one and one-quarter inch hitch receiver is used.
While the hitch receiver designs have vastly eased the problems of different vehicle designs, there are still limitations therein that manufacturers have not been able to satisfactorily address. One limitation is the variability of equipment a user will transport. Some manufacturers have addressed each different type of equipment with different add-on components which adapt the carrier to the particular equipment. Unfortunately, a store then has to stock each of the different components. The user will also have to store all of the unused components, and remember the intended purpose of each of the components. Obviously, making the carrier adaptable to a variety of cargo is an expensive proposition for all involved, and is therefore undesirable when such add-ons are required.
Another problem with hitch receiver carriers is when they support relatively large loads. The carrier is on a long arm extending from the receiver. When acceleration occurs in a vertical direction, the receiver is carrying the load exactly as it was designed for. Unfortunately, events such as acceleration, bumps and cornering lead to forces which are not always directly vertical. Particularly with the long vertical arm, forces transverse to the vehicle are amplified at the hitch. The carrier may sway or pivot undesirably within the receiver. Furthermore, even with purely vertical forces, the carrier may rattle or chatter within the receiver. Finally, there are two different standard receiver sizes that must be accommodated.
Some prior art carriers are illustrated in U.S. Pat. No. 3,437,248 to Allen, U.S. Pat. No. 4,406,384 to Schantz, U.S. Pat. No. 4,676,414 to Deguevara, U.S. Pat. No. Des. 308,846 to Eckhart, U.S. Pat. No. 5,469,997 to Carlson, and U.S. Pat. No. 5,476,202 to Lipp, the contents and teachings of each incorporated herein by reference. The Allen patent was one of the early patents which showed a multi-purpose carrier that included bicycle, ski and roof-top capability. Like many of the other subsequent patents, however, the Allen design is limited to one or two bicycles, provided the bicycles are of the right design, or, alternatively, two pairs of skis. Bicycles of unusual design, or other objects aside from the skis, are not as easily accommodated, nor are multiples of bicycles and skis.
Schantz discloses a bumper mounted carrier that includes a cargo area behind the vehicle and also on the roof-top. The Schantz design does not include adaptations for any particular type of load, but does illustrate a dual platform carrier.
Deguevara illustrates a receiver mounted bicycle carrier, with a separate attachment for carrying skis. The Deguevara patent illustrates some of the fundamental limitations discussed previously. The carrier is limited to a predetermined number and type of bicycles, two as illustrated, and requires additional hardware, purchased separately, to accommodate skis. Other equipment would require yet more hardware.
Eckhart discloses an elegantly simple bicycle carrier using rods that are inserted using cotter pins. Unfortunately, no provisions are made for other types of cargo aside from bicycles. Carlson discloses a different, yet also well devised, bicycle carrier. Unfortunately, like the Eckhart design, no provisions are made for other cargo.
Lipp discloses a bicycle and ski carrier which is capable of transporting several pairs of skis or bicycles without requiring separate add-on components, but the Lipp design is limited to carrying one type of cargo at a time, wherein the cargo must be consistent. In other words, either skis all having the same approximate thickness or bicycles having frame pieces of approximately the same diameter and having appropriate shape and dimension will fit onto the carrier, but not both simultaneously.
The prior art limitations on adaptability are particularly apparent when a larger number of bicycles, such as six, are desirably transported, particularly when those bicycles may include racing bicycles, bicycles without a top bar between seat and handle bars, and racing bicycles which may not have openings within the frame structure at all. Other difficult combinations are various assortments such as skis and bicycles or other combinations of diverse equipment.